反应详情

A mixture (S)-tert-butyl 1-(4H-benzo[d][1,3]dioxin-7-yl)-1-oxopropan-2-ylcarbamate (I3c) (680 mg, 2.21 mmol), triisopropoxyaluminum (140 mg, 0.69 mmol) and propan-2-ol (3 mL, 38.9 mmol) in toluene (3 mL) was stirred at +65° C. for 15 hours. The reaction mixture was allowed to cool down and poured into 1M HCl (50 mL) and extracted with EtOAc (2×50 mL). The organic phase was washed with water, brine, dried over MgSO4, filtered and solvents removed by evaporation to afford a crude product as a colourless solid. The crude product was first purified by Flash chromatography, (solvent A=Heptane, solvent B=EtOAc+10% MeOH). An gradient of 10% B to 50% B in A was used. The obtained product was crystallised from DCM/Heptane to afford the subtitle compound colourless needles. Yield 414 mg (60%)

1. temperatureto cool down
2. extractionextracted with EtOAc (2×50 mL)
3. washThe organic phase was washed with water, brine
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. customsolvents removed by evaporation
7. customto afford a crude product as a colourless solid
8. customThe crude product was first purified by Flash chromatography, (solvent A=Heptane, solvent B=EtOAc+10% MeOH)
9. customThe obtained product was crystallised from DCM/Heptane